Methods and systems for nulling in wireless communication networks

Abstract

Methods and systems for nulling in wireless communication networks are described herein. In one embodiment, a method performed by a first wireless communication node for initiating a nulling transmission includes: transmitting a control message to be received by a second wireless communication node, wherein the control message informs the second wireless communication node to initiate the nulling transmission toward a first station; and transmitting data to the first station during transmission of the nulling transmission from the second wireless communication node to the first station.

I/We claim: 
     
         1 . A method performed by a first wireless communication node for initiating a nulling transmission, the method comprising:
 transmitting a control message to a second wireless communication node,
 wherein the control message informs the second wireless communication node to initiate the nulling transmission toward a first station, and 
 wherein the control message causes the second wireless communication node to initiate a channel contention procedure and after successfully completing the channel contention procedure, transmit the nulling transmission; and 
   transmitting data to the first station during transmission of the nulling transmission from the second wireless communication node to the first station,
 wherein the data comprises an identification of one or more wireless communication nodes permitted to transmit the nulling transmission, and 
 wherein the one or more wireless communication nodes comprise the second wireless communication node. 
   
     
     
         2 . The method of  claim 1 , wherein the data further comprises at least one of:
 an identification of a wireless communication node;   a group identification of neighbor wireless communication nodes;   a media access control (MAC) address; or   a pair identification of one or more neighbor wireless communication nodes permitted to transmit the nulling transmission and corresponding data transmission to one or more stations.   
     
     
         3 . The method of  claim 1 , wherein a preamble or a physical layer (PHY) header of the data comprises at least one of:
 an identification indicating transmitting a nulling transmission;   one or more identifications of one or more neighbor wireless communication nodes; or   information associated with the control message.   
     
     
         4 . The method of  claim 1 , wherein the control message comprises at least one of:
 one or more identifications of one or more wireless communication nodes;   one or more group identifications of one or more wireless communication nodes;   a pair identification of one or more neighbor wireless communication nodes;   one or more MAC addresses; or   a pair identification of one or more neighbor wireless communication nodes permitted to transmit the nulling transmission and corresponding data transmission to one or more stations.   
     
     
         5 . The method of  claim 1 , wherein transmitting the data to the first station is initiated after a predetermined time period has elapsed, and
 wherein the control message indicates the second wireless communication node to initiate the nulling transmission after the predetermined time period has elapsed.   
     
     
         6 . The method of  claim 5 , further comprising:
 after transmitting the control message, receiving a response message from the second wireless communication node,   wherein the predetermined time period is determined based on a time of receiving the response message, and   wherein the nulling transmission is initiated after the predetermined time period has elapsed.   
     
     
         7 . The method of  claim 6 , wherein a first duration of a transmission from the first wireless communication node is contained in the control message and a second duration of a transmission from the second wireless communication node is contained in the response message, and
 wherein a duration of the nulling transmission is selected to be longer of the first and second durations.   
     
     
         8 . The method of  claim 1 , wherein the control message is contained in a transmission containing the data transmitted to first station. 
     
     
         9 . The method of  claim 1 , further comprising:
 transmitting the control message to the first station so as to cause the first station to transmit a response message to the second wireless communication node,
 wherein the response message indicates the second wireless communication node to select a second station based on at least one predetermined criterion, and 
 wherein a nulling operation is performed on a data transmission from the second wireless communication node to the second station. 
   
     
     
         10 . The method of  claim 9 , wherein the at least one predetermined criterion comprises whether a strength of a residual signal to be received by the first station as a result of the data transmission from the second wireless communication node to the second station is less than or equal to a predetermined threshold value. 
     
     
         11 . The method of  claim 1 , wherein the control message contains information identifying the second wireless communication node. 
     
     
         12 . A wireless communication apparatus comprising at least one processor and a memory storing instructions, execution of which by the at least one processor causes the apparatus to perform operations comprising:
 receiving a control message by a first wireless communication node from a second wireless communication node,
 wherein the control message is used to inform the first wireless communication node to initiate a nulling transmission toward a first station, and 
 wherein the control message causes the first wireless communication node to initiate a channel contention procedure and after successfully completing the channel contention procedure, transmit the nulling transmission; and 
   transmitting data to a second station during transmission of the nulling transmission to the first station,
 wherein the data comprises an identification of one or more wireless communication nodes permitted to transmit the nulling transmission, and 
 wherein the one or more wireless communication nodes comprise the second wireless communication node. 
   
     
     
         13 . The apparatus of  claim 12 , wherein the data further comprises at least one of:
 an identification of a wireless communication node;   a group identification of neighbor wireless communication nodes;   a media access control (MAC) address; or   a pair identification of one or more neighbor wireless communication nodes permitted to transmit the nulling transmission and corresponding data transmission to one or more stations.   
     
     
         14 . The apparatus of  claim 12 , wherein transmitting the data to the second station is initiated after a predetermined time period has elapsed, and
 wherein the control message indicates the first wireless communication node to initiate the nulling transmission after the predetermined time period has elapsed.   
     
     
         15 . The apparatus of  claim 14 , wherein the operations further comprise:
 after receiving the control message, transmitting a response message from the first wireless communication node,
 wherein the predetermined time period is determined based on a time of receiving the response message, and 
 wherein the nulling transmission is initiated after the predetermined time period has elapsed. 
   
     
     
         16 . The apparatus of  claim 15 , wherein:
 a first duration of a transmission from the apparatus is contained in the response message;   a second duration of a transmission from the second wireless communication node is contained in the control message; and   a duration of the nulling transmission is selected to be longer of the first and second durations.   
     
     
         17 . A first wireless communication node, comprising:
 a transceiver configured to: transmit a control message to a second wireless communication node,
 wherein the control message is used to inform the second wireless communication node to initiate a nulling transmission toward a first station, 
 wherein the control message causes the second wireless communication node to initiate a channel contention procedure and after successfully completing the channel contention procedure, transmit the nulling transmission; and 
   transmit data to the first station during transmission of the nulling transmission from the second wireless communication node to the first station,
 wherein the data comprises an identification of one or more wireless communication nodes permitted to transmit the nulling transmission, and 
 wherein the one or more wireless communication nodes comprise the second wireless communication node. 
   
     
     
         18 . The first wireless communication node of  claim 17 , wherein the transceiver is further configured to transmit the data to the first station after a predetermined time period has elapsed. 
     
     
         19 . The first wireless communication node of  claim 18 , wherein the transceiver is further configured to:
 receive a response message from the second wireless communication node after transmitting the control message,
 wherein the predetermined time period is determined based on a time of receiving the response message. 
   
     
     
         20 . The first wireless communication node of  claim 19 , wherein:
 a first duration of a transmission from the first wireless communication node is contained in the control message;   a second duration of a transmission from the second wireless communication node is contained in the response message; and   a duration of the nulling transmission is selected to be longer of the first and second durations.